Most X applications are written with the assumption that the user will
be working with a 3 button mouse. Serial mice are commonly used on
computers and are cheap to buy. Many of these mice have 3 buttons and
claim to use the Microsoft protocol, which in theory means they are
ideal for the X windows setup. (The record for the cheapest working
3 button mouse currently stands at $1.14!)

Most dual-protocol mice will work in two modes:

2-button Microsoft mode.

3-button MouseSystems mode.

This document leads you through the different steps needed to configure your
mouse in these two different modes, especially the steps needed to use the
more useful 3-button mode.

As distributions become easier to set up, some of the problems ought to go away.
For instance, RedHat have a mouseconfig program to set things up for you.
However, some versions of RH5.0 had a bug in mouseconfig, so make
sure you check for patches.